04019326 is referenced by 34 patents and cites 12 patents.

A horizontal soil drainage system consisting of a nonwoven three-dimensional mat of a plurality of looped, intersecting and substantially amorphous filaments of melt-spun synthetic polymers bonded together at their intersections, at least one of the outer surfaces of said mat having a lower cross-sectional porosity than the center zone of said mat.

Title
Nonwoven horizontal drainage system
Application Number
5/311656
Publication Number
4019326
Application Date
December 4, 1972
Publication Date
April 26, 1977
Inventor
Hans Stapp
Momlingen
DT
Jan G Vos
Dieren (Gld.)
NL
Berthold H Daimler
Remscheid-Lennep
DT
Alfred Birker
Neviges-Donberg
DT
Wilhelm Herveling
Wuppertal
DT
Agent
Jack H Hall
Francis W Young
Assignee
Akzona Incorporated
NC, US
IPC
E02B 11/00
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